A little headstrong, dignified, and always ready to lead her husband, she is the ideal young wife. She would never cheat on him. One day, a man pushes her down, hoping to get his body, but she stubbornly refuses. In the midst of her resistance, her eyes are caught by a huge cock. Kokoro is so moved by how hard it is, and from the moment it is inserted, the young wife, who was once a fine woman, stops being a human. She becomes obsessed with the other man's cock, and becomes a pervert who repeatedly has sex while constantly yelling about how it is different from her husband's cock.